U.S. patent application number 14/421643 was filed with the patent office on 2016-02-11 for transparent conductive film and fabrication method thereof, display substrate and display device.
The applicant listed for this patent is BEIJING BOE DISPLAY TECHNOLOGY CO., LTD., BOE TECHNOLOGY GROUP CO., LTD.. Invention is credited to Tengteng HU, Jinyu REN, Yongzhi SONG.
Application Number | 20160042829 14/421643 |
Document ID | / |
Family ID | 49928504 |
Filed Date | 2016-02-11 |
United States Patent
Application |
20160042829 |
Kind Code |
A1 |
HU; Tengteng ; et
al. |
February 11, 2016 |
Transparent Conductive Film and Fabrication Method Thereof, Display
Substrate and Display Device
Abstract
The present invention provides a transparent conductive film, a
fabrication method thereof, a display substrate and a display
device. The transparent conductive film includes a seed film layer
and a nano-wire film layer, and the fabrication method includes:
forming the seed film layer on the substrate by adopting a pulsed
laser deposition method, and forming the nano-wire film layer on
the seed film layer by adopting the pulsed laser deposition method.
The nano-wire film layer has a particular one-dimensional nano-wire
structure, thereby increasing the light transmittance of the
transparent conductive film to improve the utilization rate of
light energy, and quickly collecting charges and directly
transmitting the same along one-dimensional channels formed by the
one-dimensional nano-wires to improve the collection efficiency of
the charges.
Inventors: |
HU; Tengteng; (Beijing,
CN) ; REN; Jinyu; (Beijing, CN) ; SONG;
Yongzhi; (Beijing, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BOE TECHNOLOGY GROUP CO., LTD.
BEIJING BOE DISPLAY TECHNOLOGY CO., LTD. |
Beijing
Beijing |
|
CN
CN |
|
|
Family ID: |
49928504 |
Appl. No.: |
14/421643 |
Filed: |
June 30, 2014 |
PCT Filed: |
June 30, 2014 |
PCT NO: |
PCT/CN2014/081121 |
371 Date: |
February 13, 2015 |
Current U.S.
Class: |
428/216 ;
427/560; 427/596; 428/332; 428/702 |
Current CPC
Class: |
C23C 14/021 20130101;
H01B 1/08 20130101; C23C 14/086 20130101; H01L 27/124 20130101;
B82Y 40/00 20130101; C23C 14/28 20130101 |
International
Class: |
H01B 1/08 20060101
H01B001/08; C23C 14/28 20060101 C23C014/28; C23C 14/02 20060101
C23C014/02 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 21, 2013 |
CN |
201310495576.5 |
Claims
1-20. (canceled)
21. A fabrication method of a transparent conductive film
fabricated on a substrate, wherein the fabrication method
comprises: step S1: forming a seed film layer on the substrate by
adopting a pulsed laser deposition method, wherein the seed film
layer comprises uniformly distributed nano-crystalline grains; and
step S2: forming a nano-wire film layer on the seed film layer by
adopting the pulsed laser deposition method, wherein the nano-wire
film layer comprises a plurality of one-dimensional nano-wires
arranged in parallel.
22. The fabrication method of claim 21, wherein the step S1
comprises: step S11: performing ultrasonic cleaning for the
substrate by using an organic solution; step S12: drying the
substrate; and step S13: depositing and forming the seed film layer
on the substrate in an oxygen atmosphere and a room temperature
environment of a deposition chamber by using the pulsed laser
deposition method.
23. The fabrication method of claim 22, wherein the step S2
comprises: step S21: depositing and forming the nano-wire film
layer on the seed film layer in an oxygen atmosphere of the
deposition chamber by using the pulsed laser deposition method.
24. The fabrication method of claim 22, wherein the step S11
comprises: cleaning the substrate ultrasonically in an acetone
solution and an ethanol solution, each for 30-60 minutes.
25. The fabrication method of claim 22, wherein the step S13
comprises: filling oxygen in the vacuum deposition chamber so that
the pressure in the deposition chamber would be within a range of
6-10 Pa.
26. The fabrication method of claim 23, wherein the step S21
comprises: filling oxygen in the deposition chamber so that the
pressure in the deposition chamber would be within a range of 25-35
Pa.
27. The fabrication method of claim 25, wherein the purity of the
filled oxygen is 99.9% to 99.9999%.
28. The fabrication method of claim 26, wherein the purity of the
filled oxygen is 99.9% to 99.9999%.
29. The fabrication method of claim 22, wherein in the pulsed laser
deposition method, a pulsed laser transmitter is arranged outside
the deposition chamber; a focusing lens is arranged between the
pulsed laser transmitter and the deposition chamber; the deposition
chamber is provided with a transparent quartz window; a target
platform and a base platform are arranged oppositely in the
deposition chamber; a target material is arranged on the target
platform; the focus of the focusing lens, the center of the quartz
window and the center of the target material are located in the
same straight line; and the substrate is arranged on the base
platform and is parallel to the target material, wherein, the step
S13 further comprises: adjusting the distance between the focusing
lens and the quartz window to focus the focusing lens on the target
material; adjusting the distance between the target material and
the substrate to be 4.5-5.5 cm; and setting the target platform and
the base platform to rotate at the same rotating speed of 5
r/min.
30. The fabrication method of claim 23, wherein in the pulsed laser
deposition method, a pulsed laser transmitter is arranged outside
the deposition chamber; a focusing lens is arranged between the
pulsed laser transmitter and the deposition chamber; the deposition
chamber is provided with a transparent quartz window; a target
platform and a base platform are arranged oppositely in the
deposition chamber; a target material is arranged on the target
platform; the focus of the focusing lens, the center of the quartz
window and the center of the target material are located in the
same straight line; and the substrate is arranged on the base
platform and is parallel to the target material, wherein, the step
S21 further comprises: adjusting the distance between the focusing
lens and the quartz window to focus the focusing lens on the target
material; adjusting the distance between the target material and
the substrate to be 4.5-5.5 cm; and setting the target platform and
the base platform to rotate at the same rotating speed of 5
r/min.
31. The fabrication method of claim 29, wherein in the pulsed laser
deposition method, the frequency of laser pulses is 9-11 Hz, the
number of the laser pulses is 5000-7000, and the energy of a single
laser pulses is 248-252 mJ.
32. The fabrication method of claim 29, wherein the target material
adopts a transition metal oxide with a purity of 99.99%-99.9999%,
and the transition metal oxide comprises zinc oxide, tin oxide or
titanium oxide.
33. The fabrication method of claim 30, wherein the target material
adopts a transition metal oxide with a purity of 99.99%-99.9999%,
and the transition metal oxide comprises zinc oxide, tin oxide or
titanium oxide.
34. A transparent conductive film, comprising a seed film layer and
a nano-wire film layer, wherein the seed film layer comprises
uniformly distributed nano-crystalline grains, the nano-wire film
layer comprises a plurality of one-dimensional nano-wires, and the
nano-wire film layer is arranged on the seed film layer.
35. The transparent conductive film of claim 44, wherein each one
of the plurality of one-dimensional nano-wires extends on the seed
film layer in a one-dimensional manner and is arranged in parallel
to each other to form the nano-wire film layer, and the diameter of
each one of the plurality of one-dimensional nano-wires is 60-80
nm.
36. The transparent conductive film of claim 35, wherein an
included angle between each one of the plurality of one-dimensional
nano-wires and the seed film layer is 80-90 degrees.
37. The transparent conductive film of claim 34, wherein the seed
film layer and the nano-wire film layer are made of a transition
metal oxide, and the transition metal oxide comprises zinc oxide,
tin oxide or titanium oxide.
38. The transparent conductive film of claim 34, wherein the
thickness of the seed film layer is 20-50 nm, and the thickness of
the nano-wire film layer is 2-3 .mu.m.
39. A display substrate, comprising the transparent conductive film
of claim 34.
40. The display substrate of claim 39, wherein the transparent
conductive film is used as a common electrode and/or a pixel
electrode of the display substrate.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to the field of display
technology, and particularly relates to a transparent conductive
film and a fabrication method thereof, a display substrate and a
display device.
BACKGROUND OF THE INVENTION
[0002] Transparent conductive films (such as a common electrode and
a pixel electrode) in a display panel are required to not only have
good capabilities of transmitting and storing charges but also
allow light from a backlight to penetrate therethrough as much as
possible during display, in order to obtain a better display
effect.
[0003] In a traditional display panel, the transparent conductive
film is usually made of indium tin oxide material. The material
comprises many small and dense micro crystalline grains, in which a
large number of grain boundaries (i.e., contact interfaces between
crystalline grains with the same structure but different
orientations) and dangling bonds (i.e., unsaturated bonds, which
are formed by unpaired electrons on surfaces of atoms) are formed.
These grain boundaries may cracked to smaller ones in an annealing
treatment process, thus resulting in more grain boundaries. As the
grain boundaries and the dangling bonds have imperfections, the
imperfections will lead to decreased diffusion lengths of the
electrons, and therefore, the probability of recombination of
electrons and holes is increased, and a carrier recombination
center is formed, thus influencing transmission and collection
efficiencies of electrons. Moreover, the grain boundaries may have
a scattering effect on photoelectrons, which will lead to an
increased charging time of the display panel and a reduced response
speed.
[0004] Meanwhile, the transparent conductive film made of the
indium tin oxide material has a dense micro crystalline grain
structure, and it thus has a certain negative effect on the light
transmittance of the display panel. As a result, the light
transmittance of the display panel is generally less than 10%, and
the utilization rate of light energy is low.
[0005] In addition, due to the limited reserves of indium element
materials in the nature, it is urgent to develop a substitute
material for forming the transparent conductive film to replace the
indium tin oxide material, so as to further improve the yield and
reduce the product cost.
SUMMARY OF THE INVENTION
[0006] In view of the above-mentioned technical problems in the
prior art, the present invention provides a transparent conductive
film and a fabrication method thereof, a display substrate and a
display device. The transparent conductive film is fabricated by
using a pulsed laser deposition method and has a particular
one-dimensional nano-wire structure, thereby improving the light
transmittance of the transparent conductive film so as to improve
the utilization rate of light energy. Moreover, the transparent
conductive film can quickly collect charges and directly transmit
the same along one-dimensional channels formed by the
one-dimensional nano-wires so as to improve the collection
efficiency of the charges. For the display substrate adopting the
transparent conductive film, the light transmittance thereof is
greatly improved; moreover, the charging time is significantly
shortened and the response speed is greatly improved.
[0007] The present invention provides a fabrication method of a
transparent conductive film, wherein the transparent conductive
film is fabricated on a substrate, and the fabrication method
includes: [0008] step S1: forming a seed film layer on the
substrate by adopting a pulsed laser deposition method, wherein the
seed film layer includes uniformly distributed nano-crystalline
grains; and [0009] step S2: forming a nano-wire film layer on the
seed film layer by adopting the pulsed laser deposition method,
wherein the nano-wire film layer includes a plurality of
one-dimensional nano-wires arranged in parallel.
[0010] Preferably, the step S1 includes: [0011] step S11:
performing ultrasonic cleaning for the substrate by using an
organic solution; [0012] step S12: drying the substrate; and [0013]
step S13: depositing and forming the seed film layer on the
substrate in an oxygen atmosphere and a room temperature
environment of a deposition chamber by the pulsed laser deposition
method.
[0014] Preferably, the step S2 includes: [0015] step S21:
depositing and forming the nano-wire film layer on the seed film
layer in an oxygen atmosphere of the deposition chamber by the
pulsed laser deposition method.
[0016] Preferably, the step S11 includes: cleaning the substrate
ultrasonically in an acetone solution and an ethanol solution, each
for 30-60 minutes; [0017] the step S13 includes: filling oxygen in
the vacuum deposition chamber so that the pressure in the
deposition chamber would be within a range of 6-10 Pa; [0018] the
step S21 includes: filling oxygen in the deposition chamber so that
the pressure in the deposition chamber would be within a range of
25-35 Pa; [0019] the purity of the oxygen filled in the deposition
chamber in the step S13 and the step S21 is 99.9%-99.9999%.
[0020] Preferably, in the pulsed laser deposition method, a pulsed
laser transmitter is arranged outside the deposition chamber; a
focusing lens is arranged between the pulsed laser transmitter and
the deposition chamber; the deposition chamber is provided with a
transparent quartz window; a target platform and a base platform
are arranged oppositely in the deposition chamber; a target
material is arranged on the target platform; the focus of the
focusing lens, the center of the quartz window and the center of
the target material are located in the same straight line; the
substrate is arranged on the base platform and is parallel to the
target material, and the step S13 and/or step S21 further includes:
adjusting the distance between the focusing lens and the quartz
window so as to focus the focusing lens on the target material, and
adjusting the distance between the target material and the
substrate to be 4.5-5.5 cm; and moreover, setting the target
platform and the base platform to rotate at the same rotating speed
of 5 r/min.
[0021] Preferably, in the pulsed laser deposition method, the
frequency of laser pulses is 9-11 Hz, the number of the laser
pulses is 5000-7000, and the energy of a single laser pulse is
248-252 mJ.
[0022] Preferably, the target material adopts a transition metal
oxide with a purity of 99.99%-99.9999%, and the transition metal
oxide includes zinc oxide, tin oxide or titanium oxide.
[0023] The present invention further provides a transparent
conductive film, including a seed film layer, which includes
uniformly distributed nano-crystalline grains, and a nano-wire film
layer, which includes a plurality of one-dimensional nano-wires and
is arranged on the seed film layer.
[0024] Preferably, each one of the plurality of one-dimensional
nano-wires is extended on the seed film layer in a one-dimensional
manner and is arranged in parallel to each other to form the
nano-wire film layer, and the diameter of each one of the plurality
of one-dimensional nano-wires is 60-80 nm.
[0025] Preferably, an included angle between each one of the
plurality of one-dimensional nano-wires and the seed film layer is
80-90 degrees.
[0026] Preferably, the seed film layer and the nano-wire film layer
are made of a transition metal oxide, and the transition metal
oxide includes zinc oxide, tin oxide or titanium oxide.
[0027] Preferably, the thickness of the seed film layer is 20-50
nm, and the thickness of the nano-wire film layer is 2-3 .mu.m.
[0028] The present invention further provides a display substrate,
including the above-mentioned transparent conductive film.
[0029] Preferably, the transparent conductive film is used as a
common electrode and/or a pixel electrode of the display
substrate.
[0030] The present invention further provides a display device,
including the above-mentioned display substrate.
[0031] The present invention has the following beneficial effects:
the transparent conductive film fabricated by using the pulsed
laser deposition method has the particular one-dimensional
nano-wire structure, thereby improving the light transmittance of
the transparent conductive film so as to improve the utilization
rate of light energy, and thereby quickly collecting charges and
directly transmitting the same along one-dimensional channels
formed by the one-dimensional nano-wires so as to improve the
collection efficiency of the charges. For the display substrate
adopting the transparent conductive film, the light transmittance
thereof is greatly improved; moreover, the charging time is
significantly shortened and the response speed is greatly improved;
meanwhile, the transition metal oxide may be used for replacing the
indium material to form the transparent conductive film, which
improves the yield and reduces the product cost.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] FIG. 1 is a schematic diagram of a structure of a
transparent conductive film in Embodiment 1 of the present
invention;
[0033] FIG. 2 is a schematic diagram of a structure of a color
filter substrate in Embodiment 2 of the present invention;
[0034] FIG. 3 is a schematic diagram of a structure of an array
substrate in Embodiment 3 of the present invention;
[0035] FIG. 4 is a morphological structure diagram of a nano-wire
film layer fabricated in an oxygen partial pressure environment of
30 Pa;
[0036] FIG. 5 is a morphological structure diagram of a nano-wire
film layer fabricated in an oxygen partial pressure environment of
20 Pa;
[0037] FIG. 6 is a morphological structure diagram of a nano-wire
film layer fabricated in an oxygen partial pressure environment of
40 Pa.
REFERENCE NUMERALS
[0038] 1. seed film layer; 11. nano-crystalline grain; 2. nano-wire
film layer; 21. one-dimensional nano-wire; 3. first glass
substrate; 4. black matrix layer; 5. color filter layer; 6.
planarization layer; 7. common electrode; 8. columnar spacer; 9.
pixel electrode; 10. second glass substrate; 12. gate electrode;
13. gate insulation layer; 14. active area; 15. source electrode;
16. drain electrode; 17. passivation layer.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0039] In order that those skilled in the art may better understand
the technical solutions of the present invention, a further
detailed description of a transparent conductive film and a
fabrication method thereof, a display substrate and a display
device in the present invention will be given below in combination
with the accompanying drawings and specific embodiments.
Embodiment 1
[0040] This embodiment provides a transparent conductive film, as
shown in FIG. 1, the transparent conductive film includes a seed
film layer 1 and a nano-wire film layer 2. The seed film layer 1
includes uniformly distributed nano-crystalline grains 11, the
nano-wire film layer 2 includes a plurality of one-dimensional
nano-wires 21, and the nano-wire film layer 2 is arranged on the
seed film layer 1.
[0041] Specifically, each one of the plurality of one-dimensional
nano-wires 21 is extended on the seed film layer 1 in a
one-dimensional manner and is arranged in parallel to each other to
form the nano-wire film layer 2, and the included angle between
each one-dimensional nano-wire 21 and the seed film layer 1 is
80-90 degrees. The diameter of each one-dimensional nano-wire 21 is
60-80 nm. The thickness of the seed film layer 1 is 20-50 nm, and
the thickness of the nano-wire film layer 2 comprising the
plurality of one-dimensional nano-wires 21 is 2-3 .mu.m.
[0042] The seed film layer 1 has the uniformly distributed
nano-crystalline grain structures, which is favorable to forming
crystal nuclei. Based on the crystal nuclei, it is facilitated to
form the nano-wire film layer 2 having the plurality of
one-dimensional nano-wires and having a uniform structure and good
morphology. Since the nano-wire film layer 2 has the plurality of
one-dimensional nano-wires arranged in parallel, the film layer has
a uniform porosity, as a result, the light transmittance of the
transparent conductive film is greatly improved, and then the
utilization rate of light energy is improved; moreover, each
one-dimensional nano-wire forms one one-dimensional transmission
channel for photogenerated electrons. Therefore, charges are
collected quickly and are transmitted directly along the
one-dimensional channels, thus improving the collection efficiency
of the charges, and also, the grain boundaries are reduced, thus
reducing the possibility of losing the photoelectrons due to
scattering by the grain boundaries.
[0043] Preferably, the seed film layer 1 and the nano-wire film
layer 2 are made of a transition metal oxide material, and the
transition metal oxide preferably includes zinc oxide, tin oxide or
titanium oxide. By replacing the commonly used indium tin oxide
material with the transition metal oxide , the selectable range of
the materials of the transparent conductive film is further
expanded, and accordingly, the indium element material can be
replaced by the substitute material, thus improving the yield and
reducing the product cost; and meanwhile, by adopting the
transition metal oxide, the photoelectric property of the
transparent conductive film can be improved.
[0044] This embodiment further provides a fabrication method of the
above-mentioned transparent conductive film, wherein the
transparent conductive film is fabricated on a substrate, and the
fabrication method includes steps as follows.
[0045] At step S1, a seed film layer is formed on the substrate by
adopting a pulsed laser deposition method, wherein the seed film
layer includes uniformly distributed nano-crystalline grains
[0046] It should be noted that, the above-mentioned substrate may
be a substrate, such as a glass substrate or a polymer substrate,
and may also be other substrate formed with other film layer(s) and
pattern(s).
[0047] The step specifically includes: [0048] step S11: performing
ultrasonic cleaning for the substrate by using an organic
solution.
[0049] In this step, the substrate is ultrasonically cleaned in an
acetone solution and an ethanol solution, each for 30-60 minutes.
Namely, the substrate is ultrasonically cleaned in the acetone
solution for a period of time, for example, 30 minutes, and then
the substrate is ultrasonically cleaned in the ethanol solution for
a period of time, for example, 30 minutes, in order to keep the
high cleanness of the substrate to facilitate the subsequent
deposition and firm attachment of a film layer.
[0050] At step S12, the substrate is dried, and then the dried
substrate is arranged in a deposition chamber.
[0051] In this embodiment, a pulsed laser transmitter is arranged
outside the deposition chamber; a focusing lens is arranged between
the pulsed laser transmitter and the deposition chamber; the
deposition chamber is provided with a transparent quartz window; a
target platform and a base platform, are arranged oppositely in the
deposition chamber; and a target material is arranged on the target
platform; the focus of the focusing lens, the center of the quartz
window and the center of the target material are located in the
same straight line; the substrate is arranged on the base platform
and is parallel to the target material.
[0052] At step S13, the seed film layer is deposited and formed on
the substrate in an oxygen atmosphere and a room temperature
environment of a deposition chamber by using the pulsed laser
deposition method.
[0053] In this embodiment, the deposition chamber may be firstly
vacuumized to 5.0*10.sup.-8 Pa to 5.0*10.sup.-4 Pa, and meanwhile,
inside of the deposition chamber is kept at the room temperature.
For example, the deposition chamber may be firstly vacuumized to be
lower than 5 Pa by a mechanical pump, and then is vacuumized to
5.0*10.sup.-4 Pa or below by a molecular pump. Subsequently, oxygen
with a purity of 99.9%-99.9999% is filled in the deposition chamber
to change the pressure in the deposition chamber to be 6-10 Pa.
More preferably, oxygen with a purity of 99.99% is filled in the
deposition chamber to change the pressure in the deposition chamber
to 8 Pa. In addition, in this embodiment, a deposition thickness of
the seed film layer is 20-50 nm.
[0054] In this step, the distance between the focusing lens and the
quartz window may be adjusted to focus the focusing lens on the
target material, and the distance between the target material and
the substrate may also be adjusted to be 4.5-5.5 cm, and the
distance preferably is 5 cm; in addition, the target platform and
the base platform may be set to rotate at the same rotating speed,
and preferably rotate at the rotating speed of 5 r/min.
[0055] In the pulsed laser deposition method, the frequency of
laser pulses is 9-11 Hz and is preferably 10 Hz; the number of the
laser pulses is 5000-7000 and is preferably 6000; the energy of a
single laser pulse is 248-252 mJ and is preferably 250 mJ. A
transition metal oxide with a purity of 99.99%-99.9999% is used as
the target material, and the preferred purity of the transition
metal oxide is 99.99%; preferably, the transition metal oxide
includes zinc oxide, tin oxide or titanium oxide.
[0056] The pulsed laser deposition is performed under the
above-mentioned process conditions, which facilitates the formation
of the crystal nuclei, thus it can be ensured that the formed seed
film layer has uniformly distributed nano-crystalline grain
structures, so as to facilitate the subsequent formation of a
nano-wire film layer.
[0057] At step S2, a nano-wire film layer is formed on the seed
film layer by adopting a pulsed laser deposition method, wherein
the nano-wire film layer includes a plurality of one-dimensional
nano-wires arranged in parallel.
[0058] This step specifically includes: [0059] step S21: forming
the nano-wire film layer on the seed film layer in an oxygen
atmosphere of the deposition chamber by the pulsed laser deposition
method.
[0060] This step includes: filling oxygen with a purity of
99.9%-99.9999% in the deposition chamber to change the pressure in
the deposition chamber to be 25-35 Pa.
[0061] In this step, preferably, oxygen with a purity of 99.9% is
filled in the deposition chamber to change the pressure in the
deposition chamber to be 30 Pa.
[0062] In addition, preferably, an included angle between each one
of the plurality of one-dimensional nano-wires arranged in parallel
and the seed film layer is 80-90 degrees, and the thickness of the
nano-wire film layer is 2-3 .mu.m.
[0063] In this step, the distance between the focusing lens and the
quartz window is adjusted to focus the focusing lens on the target
material, and the distance between the target material and the
substrate is adjusted to be 4.5-5.5 cm, and the distance preferably
is 5 cm; the target platform and the base platform are set to
rotate at the same rotating speed, and preferably rotate at the
rotating speed of 5 r/min.
[0064] In the pulsed laser deposition method, the frequency of
laser pulses is 9-11 Hz and is preferably 10 Hz; the number of the
laser pulses is 5000-7000 and is preferably 6000; the energy of a
single laser pulse is 248-252 mJ and is preferably 250 mJ. A
transition metal oxide with a purity of 99.99%-99.9999% is used as
the target material, and the preferred purity of the transition
metal oxide is 99.99%; the transition metal oxide includes zinc
oxide, tin oxide or titanium oxide.
[0065] Under the above-mentioned process conditions, it can be
ensured that the nano-wire film layer grows approximately
vertically on the basis of the crystal nuclei in the seed film
layer, which improves the density and arrangement directionality of
the one-dimensional nano-wires in the nano-wire film layer and
ensure the nano-wire film layer to have a plurality of
one-dimensional nano-wires arranged in parallel.
[0066] It should be noted that, in the process of forming the
nano-wire film layer by adopting the pulsed laser deposition
method, the size of the oxygen partial pressure plays a crucial
role, because the oxygen partial pressure directly influences the
mean free path of metal oxide particles. An overlarge oxygen
partial pressure will lead to decreased free path of the particles,
when the free path of the particles is smaller than the distance
between the substrate and the target material, in a process of
sputtering the particles from the surface of the target material to
the substrate, the particles will collide with the oxygen molecules
for once or multiple times to have reduced energy, or form an
atomic cluster with a larger particle, thus causing a rough surface
of the film; when the oxygen partial pressure is too low, the
number of the particles arriving at the substrate is reduced, thus
influencing the deposition rate and the film forming quality.
[0067] In this embodiment, when forming the nano-wire film layer,
high-purity oxygen of 30 Pa is preferably filled in the deposition
chamber. The oxygen partial pressure of 30 Pa is appropriate, the
collision probability of the particles sputtered by laser ablation
(i.e., laser deposition) is small in the process of being
transmitted to the surface of the substrate, the particle flow rate
is desirable, and as a result, more particles can arrive at the
surface of the seed film layer with relatively large kinetic
energy. The particles arriving at the surface of the seed film
layer are apt to move to the positions where the crystal nuclei are
formed and then continuously absorb the source material, as a
result, the particles are stacked to form orderly one-dimensional
linear nanostructures by fusion. The morphological structure of the
nano-wire film layer generated at this oxygen partial pressure is
as shown in FIG. 4, the nano-wire film layer has obvious
one-dimensional morphology, an obvious backbone structure and a
moderate porosity, and therefore the light transmittance of the
transparent conductive film and the transmission rate of the
photogenerated electrons can be greatly improved.
[0068] Compared to the above-mentioned preferred oxygen partial
pressure, when forming the nano-wire film layer, if high-purity
oxygen of 20 Pa is filled in the deposition chamber, a nano-wire
film layer having a sparse nano-particle structure may be formed
only, and a nano-wire film layer having a one-dimensional nano-wire
structure approximately perpendicular to the seed film layer cannot
be formed, therefore the nano-wire film layer of this particle
structure is not suitable for serving as the transparent conductive
film, and the morphological structure diagram of the nano-wire film
layer generated at the oxygen partial pressure condition of 20 Pa
is shown in FIG. 5. In addition, if high-purity oxygen of 40 Pa is
filled in the deposition chamber, the morphological structure of a
generated nano-wire film layer is as shown in FIG. 6, it can be
seen that, with the increase of the oxygen partial pressure, the
morphology of the nano-wire film layer changes significantly. Due
to the increase of the oxygen partial pressure, the rate of the
sputtered particles is reduced, accordingly, the collision and
combination probability of the sputtered particles is increased
when being transmitted to the surface of the substrate, and as a
result, the sputtered particles are deposited on the surface of the
seed film layer in larger particles. Since the kinetic energy is
small, the particles are difficult to move in the surface of the
seed film layer, in this way, the deposition of the particles is
basically random, and a typical dendritical structure is thus
formed. This structure has a higher porosity and lacks obvious
backbone, the loose multi-branch structure will cause the
photogenerated electrons to suffer the scattering effect of a large
amount of grain boundaries in the process of being transmitted and
separated, which reduces the photoelectric energy, and then
influences the photoelectric property of the transparent conductive
film. Therefore, the nano-wire film layer of this dendritical
structure is not suitable for serving as the transparent conductive
film.
Embodiment 2
[0069] This embodiment provides a display substrate, including the
transparent conductive film in Embodiment 1. The display substrate
in this embodiment is a color filter substrate.
[0070] As shown in FIG. 2, the transparent conductive film is used
as a common electrode 7 in the color filter substrate.
[0071] In this embodiment, the color filter substrate further
includes: a first glass substrate 3, black matrix layers 4, color
filter layers 5, a planarization layer 6 and columnar spacers 8.
The black matrix layers 4 and the color filter layers 5 are
alternately arranged on the first glass substrate 3 and in the same
layer, and then the planarization layer 6, the common electrode 7
and the columnar spacer 8 are sequentially arranged on the black
matrix layers 4 and the color filter layers 5 arranged in the same
layer.
[0072] Wherein, the surface of the planarization layer 6 is smooth,
which is beneficial for the formation and firm attachment of the
common electrode 7.
[0073] Since the transparent common electrode 7 having a
one-dimensional nano-wire structure is arranged in the color filter
substrate, the light transmittance of the color filter substrate is
greatly improved, and thus the light transmittance of the entire
display panel is improved; meanwhile, since the one-dimensional
nano-wire structure forms one-dimensional transmission channels for
photogenerated electrons, charges may be quickly collected and
directly transmitted along the one-dimensional channels, thus
shortening the charging time of the display substrate and improving
the response speed thereof. In addition, the common electrode is
made of a transition metal oxide, which improves the yield and
lowers the cost of the display substrate.
[0074] In the fabrication method of the above-mentioned color
filter substrate, the common electrode 7 is fabricated by using the
fabrication method of the transparent conductive film in Embodiment
1.
[0075] The fabrication method of the color filter substrate
specifically includes: [0076] step S31: forming patterns including
the alternate black matrix layers and the color filter layers on
the first glass substrate by adopting a patterning process, and
then forming the planarization layer on the first glass substrate
with the black matrix layers and the color filter layers formed
thereon; [0077] step S32: forming the common electrode having a
plurality of one-dimensional nano-wires on the first glass
substrate subjected to step S31 by adopting a pulsed laser
deposition method; and [0078] step S33: forming a pattern including
the columnar spacers on the first glass substrate subjected to step
S32 by adopting a patterning process.
[0079] Here, the patterning process, which is the same as the
traditional patterning process, includes photoresist coating, mask
plate exposing, developing, etching, baking and other steps, and
will not be repeated redundantly herein.
[0080] The color filter substrate provided by the embodiment of the
present invention further includes an electrostatic shielding layer
(not shown in the figure) arranged on a back surface (i.e., the
other side of the first glass substrate opposite to the color
filter layers) of the color filter substrate, and a transparent
conductive film may be used as the electrostatic shield layer. The
transparent conductive film may be the transparent conductive film
provided by Embodiment 1 and is formed by the fabrication method
provided by Embodiment 1.
[0081] The display substrate in this embodiment is applicable to a
liquid crystal display device or an OLED display device of TN
(Twisted Nematic) mode or VA (Vertical Alignment) mode.
Embodiment 3
[0082] This embodiment provides a display substrate, which differs
from Embodiment 2 in that, the display substrate in this embodiment
is an array substrate. As shown in FIG. 3, the array substrate
includes the transparent conductive film in Embodiment 1.
[0083] The transparent conductive film may be used as a pixel
electrode 9 arranged in the array substrate.
[0084] In this embodiment, the array substrate further includes: a
second glass substrate 10, and a gate electrode 12, a gate
insulation layer 13, an active area 14, a source electrode 15 and a
drain electrode 16 arranged in the same layer at intervals, and a
passivation layer 17, which are sequentially arranged on the second
glass substrate 10. The pixel electrode 9 is arranged on the
passivation layer 17 and is connected with the drain electrode 16
through a via hole (not shown in FIG. 3) formed in the passivation
layer 17.
[0085] Since the transparent pixel electrode 9 of a one-dimensional
nano-wire structure is arranged in the array substrate, the light
transmittance of the array substrate is greatly improved, thus the
light transmittance of the entire display panel is improved;
meanwhile, since the one-dimensional nano-wire structure forms
one-dimensional transmission channels for photogenerated electrons,
charges may be quickly collected and directly transmitted along the
one-dimensional channels, thus shortening the charging time of the
display substrate and improving the response speed thereof. In
addition, the pixel electrode is made of a transition metal oxide,
which improves the yield and lowers the cost of the display
substrate.
[0086] In the fabrication method of the above-mentioned array
substrate, the pixel electrode is fabricated by using the
fabrication method of the transparent conductive film in Embodiment
1.
[0087] The fabrication method of the array substrate specifically
includes: [0088] step S41: sequentially forming a pattern including
the gate electrode, the gate insulation layer, a pattern including
the active area, a pattern including the source electrode and the
drain electrode, and the passivation layer on the second glass
substrate by adopting a patterning process and a deposition process
for multiple times; and [0089] step S42: forming the pixel
electrode having the one-dimensional nano-wire structure on the
second glass substrate subjected to step S31 by adopting a pulsed
laser deposition method.
[0090] In this embodiment, the patterning process is the same as
the traditional patterning process, and will not be repeated
redundantly herein.
[0091] The array substrate in this embodiment is applicable to a
liquid crystal display device or an OLED display device of TN
(Twisted Nematic) mode or VA (Vertical Alignment) mode.
Embodiment 4
[0092] This embodiment provides a display substrate, which differs
from Embodiment 2 or 3 in that, the display substrate in this
embodiment is formed by assembling a color filter substrate and an
array substrate, and both of the color filter substrate and the
array substrate include transparent conductive films.
[0093] The transparent conductive films are used as a common
electrode and a pixel electrode, wherein the common electrode is
arranged in the color filter substrate, and the pixel electrode is
arranged in the array substrate.
[0094] In the display substrate of this embodiment, the other
structures of the color filter substrate are the same as those in
Embodiment 2, the other structures of the array substrate are the
same as those in Embodiment 3, and will not be repeated redundantly
herein.
[0095] Here, the common electrode and the pixel electrode are
respectively fabricated by using the fabrication method of the
transparent conductive film in Embodiment 1.
[0096] It should be noted that, the display substrate in the
present invention refers to any substrate with a display function
or for achieving the display function, the display substrate may be
a separated array substrate, color filter substrate or opposite
substrate, or may be one formed by assembling the array substrate
and the color filter substrate or the opposite substrate.
Embodiment 5
[0097] This embodiment provides a display substrate, and the
display substrate in this embodiment is an array substrate.
Different from the embodiments 2-4, the array substrate includes a
common electrode and a pixel electrode made of transparent
conductive films.
[0098] The specific structure of the array substrate is as follows:
based on the structure of the array substrate in Embodiment 3, the
common electrode and the pixel electrode are sequentially arranged
on a passivation layer, or are sequentially arranged on the
passivation layer in a reverse sequence; the common electrode and
the pixel electrode are isolated from each other by an insulation
layer.
[0099] In this embodiment, the common electrode and the pixel
electrode are respectively fabricated by using the fabrication
method of the transparent conductive film in Embodiment 1, and will
not be repeated redundantly herein.
[0100] The array substrate in the embodiment is applicable to a
liquid crystal display device of ADS (Advanced Super Dimension
Switch) mode.
Embodiment 6
[0101] This embodiment provides a display device, including the
display substrate in any one of Embodiments 2-5.
[0102] The display device may be any product or component with a
display function, such as a liquid crystal panel, electronic paper,
an OLED panel, a mobile phone, a tablet computer, a television, a
display, a notebook computer, a digital photo frame, a navigator,
etc.
[0103] The present invention has the following beneficial effects:
the transparent conductive film fabricated by using the pulsed
laser deposition method has the particular one-dimensional
nano-wire structure, thereby improving the light transmittance of
the transparent conductive film to improve the utilization rate of
light energy, and quickly collecting charges and directly
transmitting the same along the one-dimensional channels formed by
the one-dimensional nano-wires to improve the collection efficiency
of the charges. For the display substrate adopting the transparent
conductive film, the light transmittance thereof is greatly
improved; moreover, the charging time is significantly shortened
and the response speed is greatly improved; meanwhile, the
transition metal oxide may be used for replacing the indium
material, which improves the yield and reduces the product
cost.
[0104] It may be understood that, the foregoing embodiments are
merely exemplary embodiments used for illustrating the principle of
the present invention, but the present invention is not limited
hereto. Those of ordinary skill in the art may make various
variations and improvements without departing from the spirit and
essence of the present invention, and these variations and
improvements shall fall within the protection scope of the present
invention.
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